WEBS01 Drug Resistance: A Bridge from Basic to Operations Research

1. WEBS01 Drug Resistance: A Bridge from Basic to Operations Research Pathogenesis of HIV Resistance: current knowledge and new methodologies Francesca Ceccherini Silberstein Cattedra di Virologia Università di Roma Tor Vergata

2. The emergence of resistance is the inevitable consequence of incomplete suppression of HIV replication by the current antiretroviral drugs, and is a frequent and major limitation of antiviral therapy.

3. A total of 207 deaths were identified among 1,138 participants over the followup period, with an all cause mortality rate of 18.2%. Among the 679 patients with HIV-drug resistance genotyping done before initiating HAART, HIV-drug resistance to any class was observed in 7.8% of the patients. During follow-up, HIV-drug resistance to any class was observed in 302 (26.5%) participants. Emergence of any resistance was associated with mortality (hazard ratio: 1.75 [95% CI: 1.27, 2.43]). When considered each class of resistance separately, persons who exhibited resistance to non-nucleoside reverse transcriptase inhibitors had the highest risk: mortality rates were 3.02 times higher (95% CI: 1.99, 4.57) for these patients than for those who did not exhibit this type of resistance.

4. Similarly….. Poor survival in drug-class multi-resistance 0 DCMR 1 DCMR 2 DCMR P at log-rank <0.001 3 DCMR Zaccarelli,et al., AIDS 2005

5. And….. Poor survival in drug-class multi-resistance Zaccarelli,et al., AIDS 2007

6. For treatment-naïve participants (N=1360), the risk of AIDS or death is increased for those who failed virologically with solitary NNRTI resistance and those who failed with no known drug resistance compared to those with no virologic failure. And….. Kozal,et al., HIV Clin Trials 2007

7. 2007 And…..

8. June 2011

9. In 1989 …. 4 RT mutations were associated with drug-resistance

10. Today more than 100 mutations… IAS Dec 2010 Johnson VA, et al. Top HIV Medicine 2010

11. Knowledge of HIV-1 resistance is continuously evolving During the years, with the increasing number of new PIs, the number of PR mutations associated with PI-resistance is highly increased. • IAS Evolution of HIV-1 resistance profiles follows improvements in regimens’ settings • IAS 2010 IAS and Novel

12. Genotyping resistance tests, N Improved genotypic drug resistance testing Update from Ceccherini Silberstein, et al. Clin Microbiol Infect. 2010 • More targets

13. Testing for minority resistant variants Paredes and Clotet, Eur Infect Dis 2008 • More sensitive approaches • New technologies

14. Due to the intrinsic characteristics of HIV, the selection of the first therapeutic regimen is crucial for the success of the following regimens Remember…..

15. Virological factors to be considered for a correct approach to first line therapies • Limit as much as possible the use of drugs against whom the virus has already selected primary mutations

16. Transmitted drug resistance Studies report prevalence of drug resistance in ARV-naïve patients in USA and Europe: 5 to 15% in newly diagnosed persons 10 to 25% in acutely infected persons Persistence of transmitted resistant virus (median follow-up 2.1 years) NNRTI resistance in 10/14 patients Resistant virus persistently detectable in 13/14 patients Mean time to first detectable wt/resistant mixture was 103 weeks (95% CI: 49–216) Response to therapy in patients with transmitted resistance NNRTI (n=67), PI (n=18), NRTI (n=25): some with MDR virus 45% (38/84) failed to suppress, best response in those receiving >2 active drugs (p=0.01) Little S, et al. 14th CROI, Los Angeles 2007, #60

17. Time to first virologic failure in the subcohort was substantially shorter for subjects with preexisting NNRTI-resistant virus than for those without Weighted Cox proportional hazard models including baseline NNRTI resistance showed a significantly increased risk of virologic failure for subjects with NNRTI-resistant virus at baseline compared with those without (intent-to-treat: HR, 2.27 [95% CI, 1.15–4.49]; P .018) (as-treated: HR, 2.61 [95% CI, 1.30 –5.20]; P .007) Kuritzkes et al JID 2008

19. TDR was associated with a poorer virological response when patients received cART containing ≥1 drug not fully active VF rates at M12 were 6.0% (95% confidence interval [CI]: 5.5; 6.5), 6.3% (4.2; 9.3) and 16.2% (13.0; 20.1) for no TDR group, TDR and fully active group and TDR and resistant group, respectively. Wittkop et al Lancet 2011

20. TDR was associated with a poorer virological response when patients received cART containing ≥1 drug not fully active Wittkop et al Lancet 2011

21. When an active regimen was used with TDR, the use of a 2NRTI/NNRTI combination was associated with a higher risk for VF, possibly due to the presence of minority resistant species. Wittkop et al Lancet 2011

22. Today it is possible to detect resistant quasispecies before the treatment starting. It could be important to detect as soon as possible before starting treatment Improved detection methods for HIV drug-resistance Drug-susceptible quasispecies Drug-resistant quasispecies Treatment begins Selection of resistant quasispecies • Incomplete suppression • First-line monotherapy • No Adherence • Bioavailability • Pre-existing resistance • Reservoir Viral load Time

26. While these recently developed methodologies point to the exciting potential for a new quantum of ability in the detection of ARV drug resistance, much work remains to be done to assess the clinical relevance of these “minority” variants…

27. Johnson et al Plos Med 2008

28. Simen et al JID 2009

29. Paredes et al., The Journal of Infectious Diseases 2010; 201:662–671 Halvas et al., The Journal of Infectious Diseases 2010; 201:672–680

30. Systematic Review and Baseline Characteristics Ten studies with 985 patients were identified as meeting the inclusion and exclusion criteria. The median CD4 cell count was 229 cells/mm3 and mean plasma HIV-1 RNA level was 5.0 log10 copies/mL. All studies evaluated the presence of K103N. Other commonly evaluated minority variants included Y181C (N=435) and the NRTI mutations M184V (N=228) and K65R (N=163). Low-Frequency HIV-1 Drug Resistance Mutations and Risk of NNRTI-BasedAntiretroviral Treatment Failure A Systematic Review and Pooled Analysis • Minority drug-resistant variants were found in 14% (117/808). • 35% of those with detectable minority variants experienced virologic failure • as compared to 15% of those without minority variants. Li et al JAMA 2011

31. Presence of minority variants at ≥1% conferred a significantly higher risk of virologic failure as compared to minority variants present at ≤1%. A dose-dependent effect on the risk of virologic failure was found when subjects were categorized by the absolute copy numbers of minority variants per mL of plasma. Li et al JAMA 2011

32. The detection of minority variants was associated with an increased risk of virologic failure at either high or low levels of medication adherence Li et al JAMA 2011

33. The presence of K103N mutant virus in plasma above 2000 copies/ml prior to therapy in treatment-naive individuals correlated with increased risk of virologic failure of efavirenz-containing triple-drug regimens • Multivariate logistic regression to predict risk of VF with predictors treated as categorical variables • K103N >2% was also predictive of VF with Odds Ratio = 25.5 and P = 0.0002 • Sixteen of 476 (3.4%) evaluable participants had low-level K103N at baseline by AS-PCR (0.8-15%). Svarovskaia et al XVIII Inter HIV Drug Resist 2009 Goodman et al AIDS 2011

34. Mean virological response of patients Receiving 300mg BID Maraviroc in study 1029 Change in viral load 10-30% X4 >30% X4 <10% X4 % X4 using PSSM -6.95 cut-off Swenson et al, CROI 2009, Abstract 680

35. Summary • HIV drug-resistance is both a major consequence and cause of HIV treatment failure.

36. Summary • HIV drug-resistance is both a major consequence and cause of HIV treatment failure. • Drug resistance (NNRTI and 3-class) is associated with HIV disease progression and death.

37. Summary • HIV drug-resistance is both a major consequence and cause of HIV treatment failure. • Drug resistance (NNRTI and 3-class) is associated with HIV disease progression and death. • Transmitted drug resistance is associated with a poorer virological response, particularly for NNRTI mutations.

38. Summary • HIV drug-resistance is both a major consequence and cause of HIV treatment failure. • Drug resistance (NNRTI and 3-class) is associated with HIV disease progression and death. • Transmitted drug resistance is associated with a poorer virological response, particularly for NNRTI mutations. • The presence of minority HIV-1 drug-resistance mutations is associated with more than a two times the risk of virologic failure in patients receiving an initial NNRTI-based ART regimen.

39. Summary • HIV drug-resistance is both a major consequence and cause of HIV treatment failure. • Drug resistance (NNRTI and 3-class) is associated with HIV disease progression and death. • Transmitted drug resistance is associated with a poorer virological response, particularly for NNRTI mutations. • The presence of minority HIV-1 drug-resistance mutations is associated with more than a two times the risk of virologic failure in patients receiving an initial NNRTI-based ART regimen. • The association with virologic failure was most prominent for NNRTI-resistance mutations and was dose-dependent: • ≥1% conferred a significantly higher risk of virologic failure as compared to minority variants present at ≤1%. - when subjects were categorized by the absolute copy numbers of minority variants per mL of plasma (>1000/>2000 copies/ml).

40. Conclusions • The upcoming routine availability of new and exciting technologies, such as the deep sequencing, may let scientists and clinician improve the tailoring of therapy to each single patient, by selecting those drugs and strategies able to hit at best the virus of each particular patient. • Quantity, rather than just presence, of minority resistant (or X4) quasispecies, plays a game in regulating the efficacy of NNRTI-based first line therapies (or CCR5 antagonists).

41. ACKNOWLEDGEMENTS L. Sacco University Hospital G. Rizzardini V. Micheli A. Capetti P. Meraviglia M. Moroni University of Rome “Tor Vergata” C.F. Perno V. Svicher M.M. Santoro A. Bertoli D. Armenia S. Dimonte V. Cento C. Alteri L. Fabeni R. Cammarota R. Salpini F. Stazi F. Mercurio M. Andreoni Max Planck Institute of Saarbrucken T. Sing N. Beerenwinkel T. Lengauer Virco BVBA K. Van Baelen, I. Vandenbroucke H. Van Marck, V. Van Eygen M. Van Houtte,L. Stuyver, M. Tuohy INMI “L. Spallanzani” A. Antinori P. Narciso C. Gori R. d’Arrigo F. Forbici M.P. Trotta A. Ammassari R. Bellagamba M. Zaccarelli G. Liuzzi V. Tozzi P. Sette N. Petrosillo F. Antonucci E. Boumis E. Nicastri U. Visco P. De Longis G. D’Offizi M.R. Capobianchi I. Abbate G. Rozera A. Bruselles B. Bartolini G. Ippolito San Gallicano Hospital G. Palamara M. Giuliani Resistance Study Group • The I.CO.N.A. Study Group • A. d’Arminio Monforte Infectious Diseases Unit Florence S. Lo Caputo F. Mazzotta San Martino Hospital, Genoa B. Bruzzone A. Di Biagio University of Turin G. Di Perri S. Bonora V. Ghisetti University of Catanzaro S. Alcaro A. Artese Thank you for your attention ! ISS Rome M. Ciccozzi G. Rezza S. Vella Catholic University of Rome, Sacro Cuore A. De Luca R. Cauda HôpitalPitié-Salpetrière, Paris, France V. Calvez A.G. Marcelin I. Malet P. Flandre Modena and Ferrara Infectious Diseases Center CHU de Bordeaux, France B. Masquelier C. Mussini V. Borghi L. Sighinolfi European Project CHAIN, No. 223131